Electromagnetic bell.



L. A; LITTLER. ELECTROMAGNETIC BELL.

APPLICATION FILED APR. 28, I916- Pate1ited Nov. 21,1916.

2 SHEETS-SHEET I a citizen, of the Unitedv UNITED STATES. PATENT OFFICE.

LEWIS a. times, or SHELBY, OHIO, IASSIGNOR TO THE AU'IOCALL coMrANY, or

SHELBY, OHIO, A,CORPORATION OF OHIO.

nnncrnomnsivnric BELL.

To all whom it may concern:

Be it known that I, LEwIs A. LITTLER, States, residing at Shelby, county of Richland, State of Ohio, have invented a certain new and useful Imgrovement in Electromagnetic Bells, and

eclare the following to be a full, clear, and exact description of the same, such as will enable'others skilled in the art to which it pertains to make and usethe same, reference being had to the accompanying draw-.

ings, which form. a tion. I My invention has for its object to produce a simple, compact and rugged electromagnetic bell requiring a minimum of current consumption for'its operation. The various features of novelty whereby invention is characterized part of this specificathe claims; but, for a full understanding of my invention and of its objects and advanarranged in accordance with I illustrated in tages, reference may be had to the following detailed description taken in connection with the accompanying drawings, wherein:

Figure 1 is a front elevation of a device a preferred form of my invention, with the casingor housing removed, the general box at one side through which the conductors are introduced being shown in section; Fig. 2 is a central vertical-section throughthe device .Fig. l, thecasing or housing beln in'position, Fig. 3 is a view similar toFig. 2, illustrating amodification;

Reference being hadto Figs. 1 and 2 of the drawings, plate of any suita le material, preferably of metal. In front of theupper end of the member 1 is-a gong, 2, supported on a suitable post which may conveniently consist of a bolt, 3, passing through an opening, 4:,-

in the base. plate, a spacing sleeve, 5,. and a nut, 6. If desired, a plurality. of openings, 4, may be provided so as to. permit the use of gongs 'of different diameters; the .bolt, 3, being inserted in theroper hole to bring the lower edge of t e gong in proper relation to the striking be hereinafterv described. Supported on the front side of the base plate below the gong is anelectro-magnet, preferably of the double pole type comprising two coils, 7 and 8, wound upon the arms of a U-shaped core, 9, of laminated material. The rear end. of

Specifipation of Letters Patent.

Application fllcd' April 28, 1916. Serial No. 94,131.

. Qmember. Beneath the will ,hereirti r be pointed out with particularity in" an adjustable -center line of the device projecting posts, 18,18. or outer ends of the 1 re resents a back or'base hing downwardly from the block 19,

devices to the core'is supported upon a bracket,-10, lying below the core and secured to the base member by suitable fastening screws, 11. The bracket, 10, ispreferably insulated from the-base member so as to prevent grounding of the coils through the base stationary members Patented NOV. 21', 1916.

of the electro-magnet is a post, 12, extend I ing forwardly from the base plate and, straddling the post is a aw, 13, onthe lower end of an arm, 14, lying in front: of the magnet coils. The arm is hinged, to the post, preferably by a pin, 15, fpassin through the sidemembersof the jaw an the post, thus swing from and toward th the stationary part of the The member 14' carries a which may be laminated or not, as desired, this cross piece forming the armature of. the electromagnet. A set screw, 17, passing up through the post 12 and engaging with the yoke or top piece of the e 'outer end of elcctro-rnagnet. cross piece, 16,

movement of the arm 14, thatas the movement in the, directionto carry the armature away from the core. Above the electro: magnet and on opposite. sides ofthe vertical are two. forwardly Between the front a block, 19, preferably by passing a pin, 20,

horizontally through the posts 18 and. the in any suit able manner and projecting therefrom is a 90 block 19. Fixed to the block 19 rod or stem, 21, preferably composed of spring wire. On the inner end of the mem ber 21 is a head,/22. The members 19, 21 and 22 constitute af swinging striker or hammer of which,the parts are so proportioned that-when the; hammer is. swung upwardly it strikes thegong, The block 1i lies just above the upper end of the swinging arm 14 which carries the armature and, projectust behind theupperend of the arm 14-, is a finger, 23,,which is adapted to be engaged by. a cam shaped head portion, 24, on the 11 'per end of the arm. Normally the parts he in the positions indicated in full lines in Fig. 2. When the electromagnet is energized the armature, 16, is attracted and swings inwardly so that the head,- 24, en gages with the member 23 on or hammer and the striker or hammeris permitting the member 14 toposts 18, 18, is pivoted the arm It jaw, 13, serves as support to limit the outward the striker I swung upwardly. The parts are so proportioned 'that the inward movement of the actuating member 14 is arrested before the striker engages with the gong. The result is that the last portion of the travel of the striker is a free swinging movement and there is nothing o interfere with the quick rebound of the striker after it has struck the gong.

It will be seen that all of the parts are.

of rugged construction so that the device will be extremely durable. It will also be seen that on account of the short travel of the moving parts it is possible to deliver strokes of the hammer in rapid succession which is very much to be preferred for many purposes to a more sluggish operation, while at the same time it renders the device extremely efficient and insures a low expenditure of energy. It will further be seen that the device is entirely free from springs or other elements which may easily get out of order and cause trouble, the striker and actuating arm being moved in one direction by gravity and in the other direction by the electromagnet. Even the force of the blow is controlled by the position of the set screw which limits the out- 1 Ward movement of the actuating arm and,

a vertical base plate, a gong mounted upon after the lock nut on the set screw has been tightened, the latter becomes an immovable stop not much more apt to he accidentally displaced than if it were an integral part of the base plate.

The strik'ng mechanism, including the electrodnagnct, is inclosed within a box or casing, 25, closed at its rear end by the base member and held securely against the base member by means of screws, 26, passing through the front wall of the casing and into the outer ends of the post, 12, at the bottom and a pair of similar posts, 27, at the .top. The casing is provided in the top with an opening, 28, through which the striker neau, 2:, Operates.

In Fig. 3 I have illustrated a slightly different arrangement in which the core, 9, of

the clectro-magnet lies below and is secured to a horizontal forwardly projecting web, 30, on the base member 1. Furthermore, the striker or hammer, 31, including the downwardly projecting cam 32, is made in a single piece.

'1 claim: I

1. In a device of the charaeter described,

and in front of the upper portion of the base plate, a striker mounted on the base plate below the gong so as to swing in'a vertical plane at right angles to the plane ofthe base plate toward and from the gong, an electromagnet mounted on the base-plate below the striker, a swinging arm extending upwardly in front of the electro-maguet, an armature on said arm adapted to-be attracted by the -electro-magnet, and cooperating parts on the electro-magnet is energized and drive the striker toward the gong.

2. In a device of the character described, a base plate, a gong lying in front of and secured to one end of the base plate, posts projecting forwardly from the base plate below the gong, a striker pivotally supported at one end by said posts, an electro-magnet lying beneath said posts and rigidly con nected to the base plate, a third post projecting forwardly from the base plate bcneath the electro-magnct, an arm hinged to the latter post and projecting upwardly in front of the electro-magnet into the vicinity of the striker, an armature on said arm, and cooperating parts on the arm and on the striker engaging with each other but having no connection with eachother and adapted to cause the striker to be driven toward the gong when the electro-magnet is energized.

In a device of the character described,

I a base plate, a gong mounted upon one end lower end to said second post and projecting upwardly in front of the elcctro-magnet to the striker, an adjustable stop between said arm and the post on which the arm is mounted, the stop being adapted to limit the movement of the arm in the outward direction, an armature on said arm, and coiiperatin faces between the upper end of the arm and the striker for causing the striker to be propelled toward the gong when the electromagnet is energized. I 4. in a dcdcc of the diameter described, a base plate, a gong mounted upon and in front of the upper end of the base plate, a post projecting forwardly from the base plate beneath the gong, a striker lying beside the post and ha'vmg a gong engaging part at its inner end, a pivotal connection between theouter end of the striker and the aforesaid post for permitting the striker to swing in a vertical plane, the striker having a downwardly projecting part near the outer end, an actuator lying in front of said part and having a cam face for engagement therewith, said actuator being moved in one direction by the weight of and lying in front of the upper end of the base plate, a striker mounted on the base plate below the gong so as to be freel inovable in a vertical. plane at right angles to the plane of the base plate from and toward the gong, an ele'ctro-magnet secured to the base plate below the striker with the core thereof extending forwardly at right angles to the base plate, an armature movably supported in front of the electro-magnet, and a part associated with said armature having .no

connection with the striker but siinpl r-ontacting therewith for throwing the striker upwardly against the action of gravity in order to engage the gong. p

6. in a. device of the character described.

a vertical base plate, a gong mounted upon and lying in front of the upper end of the ba'se plate, an electro-maginet secured to and projecting forwardly from the base plate at a point below the. gong, a striker mounted on the base'plate.between the gong and elem tro-luagznet so as to be capable of swinging 111 a vertical plane, an armature inovably supported by the base plate in front of said In testimony whereof, I sign this specification.

LEWIS A. LITTLER. 

